Can sorting device



y 1964 T, MIZELL, JR., ETAL 3,131,816

CAN SORTING DEVICE 2 Sheets-Sheet 2 Filed May 15, 1961 P UJER SOURCE MAIN AMPLIFIER AH D ELECTRONIC RELAY PR EAMPLI FIER SIGNAL DISCRIMIHATOR United States Patent 3,131,816 CAN SSRIENG DEVICE Toney Mizell, 3n, and Sherwood E. Houser, Modesto, Calif. Filed May 15, 3.961, Ser. No. 11%,963 7 Claims. (Q1. 299-1115) This invention relates in general to apparatus employed in the food canning industry.

In such industry use is now commonly made of a continuous process retort, but due to the resultant increased efiiciency and shortened cooking time an average size cannery cannot economically process only one kind or grade of canned product through the retort at a time. It is thus the practice to feed the cans, irrespective of the kind or grade of product therein, in intermingled relation through the retort and to thereafter segregate such cans, by indicia thereon, into separate runs corresponding to said kinds or grades of products.

The task of so segregating the cans manually is most difiicult and impractical, especially when several hundred cans per minute must be handled. Certain automatic devices for the purpose have heretofore been developed, but thesebecause of structural and functional problemshave not been wholly successful, and hence have not found substantial acceptance in the industry.

it is therefore the major object of this invention to provide a can sorting device which, in association with a conveyor carrying intermingled but pro-marked cans, is operativeeveu at relatively high speed-to accurately and positively segregate the cans according to said premarking thereof; i.e., to divert from said conveyor, according to a certain pre-marking, all cans of one kind or grade of product, While permitting the remaining cans, with other pro-markings, to continue to advance with said conveyor. Thus, in practice, and with separate ones of the devices mounted at successive stations along the conveyor, complete and effective segregation of the cans into separate and proper runs can be accomplished.

Another object of the invention is to provide a can sorting device adapted for use in cooperation with conveyor supported cans on winch the pro-marking consists of a plurality of circumferentially spaced serrations or notches formed in one of the can beads, with a difierent spacing of the notches on the cans of each kind or grade of prodnot; the device being operative to sense those cans having notches with a certain spacing and to segregate such cans by diverting them from the conveyor.

An additional object of the invention is to provide a can sorting device, for cans pre-marked as described in the preceding paragraph, which includes a novel transducer unit including a stylus which vibrates in response to engagement with the notched head of each passing can; such vibrations in the present embodiment being electromagnetically translated into electrical oscillations of a proportionately related frequency, and the can sorting mechanism of the device being controlled by such oscillations and dependent on the frequency thereof.

it is also an object of the invention to provide a practical and reliable can sorting device, and one which will be exceedingly erfective for the purpose for which it is designed.

These objects are accomplished by means of such structure and relative arrangement of parts as will fully appear by a perusal of the following specification and claims.

In the drawings:

FIG. 1 is a top plan of the can sorting device as in use.

FIG. 2 is a transverse enlarged sectional elevation on line 2--2 of FIG. 1.

FIG. 3 is an enlarged front elevation, partly broken awa of the transducer unit.

3,131,816 Far-tented May 5,, 1964 ice FIG. 4 is a sectional bottom plan View of the transducer unit taken on line 44 of FIG. 3.

FIG. 5 is an enlarged fragmentary transverse sectional elevation on line 5-5 of FIG. 1.

FIG. 6 is an enlarged fragmentary sectional View on line 6-6 of FIG. 4.

FIG. 7 is a schematic outline of the electronic system employed between the transducer unit and the can diverting electro-magnet.

Referring noW more particularly to the drawings and to the characters of reference marked thereon, the device comprises a conveyor, indicated generally at 1, adapted to support and advance a row of cans Z disposed in singlefile order on and advanced by a conveyor belt 3 bordered by upstanding, can guiding side plates 4 and 5; the cans standing on end.

termediate the ends of the conveyor 1 the side plate 5 is formed with a gate 6 dimensioned to permit the passage of a can 2 laterally off of the conveyor belt 3. It is through this gate 6 that certain of the cans are diverted during the segregating or sorting operation, and as each can passes through the gate 6 it tilts oil of the conveyor belt 3, is received on and slides down a laterally extending rounded incline 7, and thence falls into a carry-off chute 8. Guide rods 9 assure of proper entry, Ofeach diverted can, into the chute 8 after passing through the gate 6.

A can diverting electro-rnagnet It? is mounted on a platform 11 disposed immediately beyond the receiving end of the chute 8; such electro-magnet 1% including a pair of vertically alined core arms 12 which extend at a forward and inwmd diagonfl to a free end termination immediately at the adjacent end of the gate 6 and in position to contact each can 2 just before it reaches said gate. The outer or free ends of the core arms 12 are rounded, as shown at 13.

For the purpose of illustration, the cans 2 are identified by the letters A and B; such cans A and Bcontaining products of different grades or kinds. Each of the cans 2 is formedon the under side of the uppermost head 14, and all about the same-with a plurality of circumferentially spaced serrations or notches 15; the number of notches on the cans A being diiferent than the numher on the cans B; i.e. with diiferential spacing.

Opposite the can diverting electro-magnet 1ll-i.e. on the opposite side of the conveyor-there is a can engaging transducer unit, indicated generally at 16; such transducer unit being elongated and extending at a forward and inward diagonal and in a horizontal plane for engagement with the uppermost bead 14 of each can 2 at a point substantially transversely alined with the rounded free ends of the core arms 12 of said electro-magnet 10.

The construction and operation of the can engaging transducer unit will be hereinafter described in detail. However, for the present it suffices to understand that such transducer unit 16 is operative to sense the spacing of notches 15 in the uppermost head 14 of each passing can 2. The eleotro-magnet iii is normally energized but is controlled-i.e. remains energized or is deenergizedin response to the transducer unit 16.

When each can A is engaged by the transducer unit 16, with the latter sensing the spacing of notches 15 in the uppermost head 14 of said can, the electro-magnet It remains energized and the rounded free ends 13 of core arms 12 maintain a magnetic hold on said can. Then, with the continued advance of the conveyor belt 3, such can A-under the influence of the moving belt, together with said magnet holdis swept laterally, riding about the rounded ends 13 of the core arms 12 and passing through the gate 6, as shown in dotted lines in FIG. 1. When the can thus passes through-the gate 6 it tilts oif the belt and gravitationally breaks away from the rounded ends 13 of core arms 12, whence the can traverses the incline 7 and falls int othe chute 8.

When each can B is engaged by the transducer unit 16, with the latter sensing the different predetermined spacing of notches 15 in the uppermost bead 14, the electromagnet Ill-under the. control of said transducer unit is deenergized and said can remains on the conveyor belt 3 and passes gate 6 without being diverted.

In the foregoing manner cans with differentially prenotched beads are accurately and positively segregated, and which can be accomplished at relatively high speed. The transducer unit 16 is constructed, and functions to control the electro-magnet 10, as follows:

Said transducer unit 16 comprises an elongated hollow sheet metal arm 17 which through the major portion of its length is rectangular in cross section; such arm being disposed at a forward and inward diagonal. On the outer side and adjacent its rear end the arm 17 is attached by screws 18 to a horizontal mounting block 19 journaled on the upper end of a vertical post 20 by means including bearings 21. The post 20 upstands from a housing 22, and which housing encloses parts of the electronic system, as indicated in FIG.,7.

The arm 17 is normally but yieldably urged in a direction tending to swing its forward end inwardly; this being accomplished by a compression spring 23 engaged between the mounting block 19 at a point ahead of the axis of post 20, and an outwardly disposed upstanding flange 24 included in a bracket 25 secured to the post 20 by a collar. 26. The upstanding flange 24 also carries a stop screw 27 positioned to adjustably limit the extent of inward swinging movement of the forward end of the arm 17.

The forward portion of the arm 17 on the side adjacent the conveyor 1 is open, and a flat, elongated, dielectric bar 28 is mounted in the forward portion of said arm in spaced relation to the top and bottom thereof, except that said top and bottom-at their outermost ends-are bent down to form ears 29 between which the adjacent part of said bar is clampingly engaged. The bar 28 is of a configuration and length such that the side edge adjacent the conveyor as well as the rounded front end of said bar are exposed beyond the arm 17 for can head engagement; there being a longitudinal groove 30 in the exposed edge of the arm adapted for can bead reception, and with such groove extending into the rounded front end of the bar. a

The arm 17, as swingably mounted on the post 20, is disposed in a horizontal plane such that the uppermost bead 14 of each passing can will engage in and ride along the groove 30. Within the forward portion of arm 17 thebar 28 is formed with a cut-out or cavity 31 which receives the coil 32 and its included core 33 of a magnetic type impulse generator, indicated generally at 34.

The impulse generator 34, in addition to the coil 32 and core 33, embodies pole pieces or plates, indicated at 35 and 36; such pole pieces or plates 35 and 36 having extended portions separated by a pair of superimposed dielectric spacers 37;v Bolts 38 secure the assembly of the pole pieces or plates 35 and 36 and the dielectric spacers 37 to the bar 28, whereby to also support the coil 32 and core 33 of the impulse generator 34 in clearance relation to the arm 17. V a p In addition to the foregoing parts, the impulse generator 34 includes a vibratory magnetic finger 39 clamped between the dielectric spacers 37 and thence extending longitudinally in a forward direction to a free end ter- In order to assure that the finger 39 remains magnetized at all times a small permanent magnet 43 is mounted in the bar 28 in adjacent but spaced relation to said finger 39 a short distance ahead of the inturned tips 42.

A pair of leads 44 extend from the coil 32 rearwardly in the hollow arm 17 and connect to a jack unit 45 which includes a plug 46 coupled to a two-wire cord 47. The cord 47 leads into the housing 22, and within the latter is coupled to a pre-amplifier 48 which feeds a signal discriminator 49, with the latter coupled in input relation to a main amplifier and electronic relay 50; the power source being indicated at 51. a

As the pre-amplifier 48, signal discriminator 49, and main amplifier and electronic relay 50 embody well known electronic principles and circuitry, a detailed disclosure of the circuitsand which may take various forms-is unnecessary.

A two-wire cord 52 leads from the main amplifier and electronic relay 50, out of the housing 22, and thence extends to connection with the electro-magnet 10.

The electronic relay, associated with the main amplifier, normally maintains the electro-magnet 10 energized.

As each can 2 advances, its uppermost bead 14 engages in and rides along the groove 30; the resultant contact of the .stylus 40 with the notched under side of said can bead producing mechanical vibration of finger 39 with a frequency corresponding to the spacing of the notches 15. With such mechanical vibration of finger 39 between the tips 42 of the pole pieces or plates 35 and 36, such vibrations are transduced into magnetic oscillations in core 33 and a current of the same frequency is inducedor generated in the coil 32.

With the conveyor belt 3 moving at a constant speed, the frequency of the current fed from the coil 32 will vary, depending on the spacing of the notches 15 in the uppermost head 14 of the can engaged by the transducer unit 16.

In other words, cans A and B will produce difierent frequency responses, and these are employed to control the electro-magnet 10. More particularly, the induced current is fed from the transducer unit 16 through leads 44 and cord 47 to the pre-amplifier 48, and thence to the signal (or frequency) discriminator 49.

The signal discriminator 49 is. set so that when the current frequency is that derived from and corresponds to a can A, as engaged by the transducer 16, the main amplifier and electronic relay 50 do not function to open or break the current supply circuit to electro-magnet 10. Consequently, such can A is diverted from the conveyor and segregated, as previously described.

However, when the current frequency is that corresponding to and produced by a can B passing in engagew ment with the transducer unit 16, the signal discriminator 49 functions to cause the main amplifier and electronic relay 50 to open the .circuit to the electromagnet 10, whereupon the latter is deenergized and said can B remains on and continues to advance with the conveyor, also as previously described.

mination in an upturned stylus 40. The stylus 40 projects in clearance relation into a recess 41 in. the bar 28 and so that the tip of such stylus is exposed in the groove 30 intermediate the ends thereof. Between the dielectric spacers 37 and the stylus 30 the vibratory magnetic finger 39 passes between but remains spaced from intur'ined tips 42 formed on the pole pieces or plates 35 an 36.-

Thus, with the sensing by the transducer unit 16 of the differential spacing of the bead notches of cans A and B passing on the conveyor between the electromagnet 10 and said transducer unit 16, and with control of said electro-magnet by variance in the current frequencies as fed from such transducer unit, positive and accurate can sorting is accomplished with the present device.

While the foregoing description refers to the sorting by a single device of cans containing two different kinds or grades of products, it will be evident that when the cans contain more than two diiferent kinds or grades of prod ucts, and with the cans diiferentially marked or beadno tched correspondingly, selective segregation can be readily attained by merely employing separate sorting devices at spaced stations along the conveyor, with each such device set to divert only cans containing a like product.

From the foregoing description it will be readily seen that there has been produced such a device as will substantially fulfill the objects of the invention, as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described the invention, the following is claimed as new and useful, and upon which Letters Patent are desired:

1. A can sorting device comprising a conveyor adapted to support and advance cans in a single file, each can being formed with a row of deformations in like position but with differential spacing corresponding to the kind or grade of product in the can, means to divert individual cans from the conveyor, a can sensing unit mounted adjacent the conveyor in a predetermined position relative to the can diverting means, said sensing unit including a vibratory element contacting each passing can along the row of deformations and being caused to vibrate thereby, and means responsive to the frequency of vibration of said element operative to control said can diverting means; the cans being disposed on end on the conveyor, the deformations being spaced notches in a head of each can, and said element being a bead engaging stylus; the notched bead being on the upper end of each can, the notches being on the under side of the bead and the stylus upstanding from below into engagement therewith.

2. A can sorting device comprising a conveyor adapted to support and advance cans in a single file, each can being formed with a row of deformations in like position but with differential spacing corresponding to the kind or grade of product in the can, means to divert individual cans from the conveyor, a transducer unit mounted adjacent the conveyor in a predetermined position relative to the can diverting means, said transducer unit including an electrical impulse generator having a vibratory finger, vibration of the finger being translated by said generator into electrical impulses of corresponding frequency, the cans being disposed on end on the conveyor and the row of deformations being in the uppermost bead of each can, the vibratory finger having a stylus positioned to contact such bead of each passing can along the row of deformations whereby the finger is caused to vibrate, and means responsive to the frequency of the resultant electrical impulses operative to control said can diverting means; the transducer unit including an arm extending at a forward and inward diagonal to closely adjacent the path of the cans on the conveyor, a member on the forward end of the arm having a longitudinal groove in which the uppermost head of each passing can tracks, there being a recess in the member open to the groove, and the stylus projecting into the groove for can bead contact.

3. A device, as in claim 2, including means mounting the arm for movement about an upstanding axis, and means yieldably urging the arm about such axis in a direction to maintain said member in engagement with each passing can.

4. A can sorting device comprising a conveyor adapted to support and advance cans on end and in single file, upstanding can-guide plates along the sides of the conveyor one of which plates has a can-receiving gate therein, each can being provided with a circumferential row of deformations in like position but with differential spacing corresponding to the kind or grade of product in the can, an electromagnet mounted laterally out from the conveyor on the gate side thereof and including a core arm projecting to a free rounded-end termination at the rear end of the gate and extending at a forward angle to the conveyor, a sensing unit on the opposite side of the conveyor laterally out therefrom and including a vibratory element contacting each passing can along the row of deformations and being caused to vibrate thereby, means responsive to the frequency of vibration of said element to control the functioning of the electromagnet, a movable horizontal arm which adjacent one end contacts each can in turn at a point opposite said free end of the core arm and on which the sensing unit is mounted, and a spring yieldably acting on the arm to urge said one end thereof against the can.

5 A device, as in claim 4, in which the arm is hollow and the sensing unit is enclosed therein.

6. A device, as in claim 4, in which the row of deformations is on the under side of the upper bead of the can; the arm contacting such bead and the vibratory element engaging the row of deformations from below the point of contact of the arm with said bead.

7. A can sorting device comprising a conveyor adapted to support and advance cans on end and in single file, upstanding can guide plates along the sides of the conveyor one of which plates has a can-receiving gate therein, each can being provided with a circumferential row of deformations in like position but with differential spacing corresponding to the kind or grade of product in the can, an electromagnet mounted laterally out from the conveyor on the gate side thereof and including a core arm projecting to a free rounded-end termination at the rear end of the gate and extending at a forward angle to the conveyor, a sensing unit on the opposite side of the conveyor laterally out therefrom and including a vibratory element contacting each passing can along the row of deformations and being caused to vibrate thereby, means responsive to the frequency of vibration of said element to control the functioning of the electromagnet, a horizontal arm extending at an acute forward angle to the conveyor and terminating at its forward end opposite said free end of the core arm, means vertically pivoting the arm intermediate its ends for swivel movement relative to the conveyor, the row of deformation being on the upper bead of the can, a dielectric bar secured in the arm and having an end-edge portion projecting from said one end of the arm and from the adjacent portion of that side edge thereof which faces the cans, said edge portion of the bar be ing convexly curved and having a groove therealong to engage said head of a can and the bar having a recess leading to the groove through which the vibratory element projects and a spring acting on the arm to yieldably maintain the bar in contact with the can.

References Cited in the file of this patent UNITED STATES PATENTS 2,494,438 Gilbert Jan. 10, 1950 2,563,413 Ostrow Aug. 7, 1951 2,778,497 Bickley Ian. 22, 1957 2,817,438 Birchall Dec. 24, 1957 2,989,735 Gumpertz June 20. 1961 

1. A CAN SORTING DEVICE COMPRISING A CONVEYOR ADAPTED TO SUPPORT AND ADVANCE CANS IN A SINGLE FILE, EACH CAN BEING FORMED WITH A ROW OF DEFORMATIONS IN LIKE POSITION BUT WITH DIFFERENTIAL SPACING CORRESPONDING TO THE KIND OR GRADE OF PRODUCT IN THE CAN, MEANS TO DIVERT INDIVIDUAL CANS FROM THE CONVEYOR, A CAN SENSING UNIT MOUNTED ADJACENT THE CONVEYOR IN A PREDETERMINED POSITION RELATIVE TO THE CAN DIVERTING MEANS, SAID SENSING UNIT INCLUDING A VIBRATORY ELEMENT CONTACTING EACH PASSING CAN ALONG THE ROW OF DEFORMATIONS AND BEING CAUSED TO VIBRATE THEREBY, AND MEANS RESPONSIVE TO THE FREQUENCY OF VIBRATION OF SAID ELEMENT OPERATIVE TO CONTROL SAID CAN DIVERTING MEANS; THE CANS BEING DISPOSED ON END ON THE CONVEYOR, THE DEFORMATIONS BEING SPACED NOTCHES IN A BEAD OF EACH CAN, AND SAID ELEMENT BEING A BEAD ENGAGING STYLUS; THE NOTCHED BEAD BEING ON THE UPPER END OF EACH CAN, THE NOTCHES BEING ON THE UNDER SIDE OF THE BEAD AND THE STYLUS UPSTANDING FROM BELOW INTO ENGAGEMENT THEREWITH. 